| 摘要 |
PURPOSE:To develop a composite high alloy-steel roll having neck parts excellent in toughness by reasonably improving the shapes and dimensional ratios and the material at each part of a rolling roll. CONSTITUTION:A roll used for hot strip rolling is so formed that its neck length lN is larger and its body diam. DB is smaller than those of conventional ones, and the ratio lN/lB between the neck length lN and the body length lB is 0.8-1.2, and the ratio lN/DN between the length lN and the neck diam. DN is 3.8-13.0. In manufacturing the roll, a body outer-shell part 4 required to have resistances to wear, surface roughening, and crack is manufactured by casting a high-alloy grain material by using a quenching mold such as a metallic one, and a slow cooling mold such as a sand one is used for a neck part 5 required to have toughness. Further, a ductile cast iron or a graphite steel is used for a body axial part 6 and a neck part 5, which are cast into one body to form a blank material of composite roll. The material after rough machining is hardened by an intermediate frequency hardening device and is machined for finish forming it. |
